Trends in photoresist materials for extreme ultraviolet lithography: A review

With the development of microelectronics, the demand for continuously miniaturized feature sizes has driven continuous progress in lithography technology. Extreme ultraviolet (EUV) lithography can directly pattern sub-20-nm half-pitch resolution, and it has emerged as the most promising nanoscale fabrication technology. However, the restricted brightness of the EUV light source and the limited reflectivity of multilayer mirrors impose new requirements for the sensitivity of photoresists. Furthermore, the high-resolution patterning characteristics of the EUV require resistive materials featuring smaller component sizes and higher etch resistance. Thus, the development of photoresists with new attributes of EUV remains a challenge. This review covers the evolution of EUV photoresists, including chemically amplified resists, non-chemically amplified polymer resists, molecular glass resists, and metal-containing resists, including the future development trends of EUV-sensitive materials.